Question

I’m trying to read data from a socket, however whenever I try to read the entire stream my program hangs. With no error or exception.

I can manually read say 4 bytes and it will work, however I no longer know the exact size of the data the server will send, therefore I wish to read the entire stream. What am I doing wrong?

It hangs when calling ReadToEnd().

Stream input = socket.GetStream();

byte[] request = new byte[5];

input.Write(request, 0, 5); //send request

StreamReader reader = new StreamReader(input);

if (input.CanRead == true)
{
    string test = reader.ReadToEnd();
}

Answer 1

Your code canot know how long the stream is, it’s possibly not ended so its going to continue to block until it has. Below is an example server and client (in no way is this a robust implementation) but if you consider the following code you should see how to send a request and receive a response:

    public class Server
    {
        private readonly Thread _listenThread;
        private readonly TcpListener _tcpListener;

        public Server()
        {
            _tcpListener = new TcpListener(IPAddress.Any, 3000);
            _listenThread = new Thread(Listen);
            _listenThread.Start();
        }

        private void Listen()
        {
            var tcpListener = _tcpListener;

            if (tcpListener != null)
            {
                tcpListener.Start();
            }

            while (true)
            {
                TcpClient client = _tcpListener.AcceptTcpClient();
                Console.Out.WriteLine("Connection Accepted");
                Thread clientThread = new Thread(DoWork);
                clientThread.Start(client);
            }
        }

        private void DoWork(object client)
        {
            TcpClient tcpClient = client as TcpClient;

            if (tcpClient == null)
            {
                throw new ArgumentNullException("client", "Must pass client in");
            }

            using (NetworkStream clientStream = tcpClient.GetStream())
            {
                byte[] message = new byte[1024];

                while (true)
                {
                    Console.Out.WriteLine("Waiting for message");
                    int bytesRead = clientStream.Read(message, 0, 1024);

                    if (bytesRead == 0)
                    {
                        break;
                    }

                    ASCIIEncoding encoder = new ASCIIEncoding();
                    string received = encoder.GetString(message, 0, bytesRead);

                    Console.Out.WriteLine(String.Format("Read {0}", received));
                    if (received.Equals("Hello Server !"))
                    {
                        byte[] buffer = encoder.GetBytes("Hello Client!");
                        clientStream.Write(buffer, 0, buffer.Length);
                        clientStream.Flush();
                    }
                }
            }
        }
    }

You would need a client that did something like this

    static void Main(string[] args)
    {
        try
        {

            using (TcpClient clientSock = new TcpClient(IPAddress.Loopback.ToString(), 3000))
            {
                using (Stream clientStream = clientSock.GetStream())
                {
                    ASCIIEncoding encoder = new ASCIIEncoding();
                    byte[] helloMessage = encoder.GetBytes("Hello Server !");

                    clientStream.Write(helloMessage, 0, helloMessage.Length);
                    clientStream.Flush();

                    using (StreamReader streamReader = new StreamReader(clientStream))
                    {
                        while(true)
                        {
                            char[] buffer = new char[1024];
                            streamReader.Read(buffer,0, 1024);

                            Console.Out.WriteLine(new string(buffer));
                        }
                    }
                }
            }

            Console.ReadLine();
        }
        catch (Exception)
        {
            // do something here

            throw;
        }
    }